Spreadsheets are everywhere, they are the most used systems in the history of computing. That is due
to the very wide variety of usage of them. Moreover, it is more convinient for small companies to use spreadsheets
as a small database system to keep the needed data. However, the lack of semantics of spreadsheet makes a huge obstacle
to put a base that everyone can build up on. Moreover, the limited amount of research that is done over spreadsheets does not
make us know the real full potential of using them.

In this paper we will propose a method to convert UML \textit{(Unified modelling language)} diagrams
\cite{rumbaugh1999unified} and CM \textit{(Conceptual models)} \cite{brodie1984conceptual} into
spreadsheets. Since UML diagrams and conceptual models have predefined semantics, it is more easy to interpret them. Then, we try
to encode the constraints that should be enforced over the models.

The main idea behind this work is that we try to convert the UML diagrams and the CMs into a relational model. Afterwards, we
obtain a set of spreadsheets \textit{(workbook)} from this relational model.

In the first part of this paper, we will show how to convert from UMLs and CMs into relational models. After this, we show the
idea of the conversion from relational models to spreadsheets. 